1. Field of the Invention
The present invention relates to a cord switch which is switched over when a cord member of the cord switch is pressed.
2. Description of the Related Art
Considering the safety for the user of the vehicle, a window regulator which is driven by a motor to raise and lower a glass of a vehicle door, for example, has been provided in which a cord switch is mounted on a window frame of the vehicle door, and when any obstacle (or foreign object) has been jammed between the cord switch and the glass of the vehicle door, the cord switch is pressed and switched over, so that rotation of the motor is stopped or reversed.
As shown in FIG. 14, a cord switch 60 has a hollow flexible cord member 62 such as a silicone, a rubber or the like in which the cord member 62 is provided with contact lines 64 at an upper wall portion 62A (which corresponds to one of two wall portions of the cord member 62 generally opposed to each other) and at a lower wall portion 62B (which corresponds to the other of the two wall portions), respectively. When the cord member 62 is pressed, these contact lines 64 are made contact each other.
However, when the cord switch 60 is mounted on the window frame of the vehicle door, it may be bent largely at the corner of the window frame. Therefore, the contact lines 64 may be made to contact each other when the cord switch 60 is mounted on the window frame.
Therefore, in a cord switch 72 shown in FIG. 15, a bridge conductor 68 is disposed at an upper wall portion 66A of a cord member 66 and two contact lines 71 are disposed at a lower wall portion 66B of the cord member 66 with a barrier wall 70 being interposed between these contact lines 71 (see Japanese Utility Model Application) No. 5-41282).
The cord switch 72 is structured such that even when a bending force is applied to the cord switch 72, because the distal end portion of the barrier wall 70 abuts on the bridge conductor 68, the bridge conductor 68 and the contact lines 71 are not made to contact each other unnecessarily.
However, unless a pressing force which acts on the cord member 66 is strong enough to deform the barrier wall 70, the bridge conductor 68 does not contact these contact lines 71. Further, when the pressing force acts on the barrier wall 70 vertically, the bridge conductor 68 is pressed in parallel to the barrier wall 70 and does contact the contact lines 71. However, if the pressing force acts on the barrier wall 70 from a transverse or diagonal direction, the barrier wall 70 is not deformed but is inclined due to the pressing force, and the bridge conductor 68 is pressed diagonally, so that the bridge conductor 68 does not contact any of the contact lines 71.
In view of the aforementioned facts, it is an object of the present invention to provide a pressure-responsive safety cord switch in which the desired bendability of the cord switch is accomplished, a contact portion and a contact body are not made to contact each other even when the cord switch is bent or flexed, but the contact portion and the contact body are made to contact each other even when a pressing force which acts on the cord switch is relatively small, and the contact portion and the contact body are made to contact each other, regardless of the angle at which the cord switch is pressed.